i am studying and and staying out of my house(hostel).how to improve my sexual health?

Is there is a relation between morning wood and sexual health? i mean if a guy wake up with morning wood, is it a sign that he is phyiscaly ok and can have sex well? or he may have morning wood but still has sexual dysfunction. and if a guy doesnt have morning wood , it means he is not ok?

On saturday night sucked my boyfriends penis, and now its sunday night and im urinating alot more than i usually do. Is that a sign i have a std? If so, which one?

I had a condom slip off once during sex, and duing my next period I had worse cramps than normal. Is this a possible sign of an std? If so, which ones?

You don’t need to tell me to get tested, I am planning on it. But I was just wondering if you know this to be a symptom or if there could be another cause.